92 5.0 Idle Surge

[KaLiKo Street]

I just recently put a 5.0 out of a 90 Mark VII into my 92 2.3 Mustang. The 5.0 run perfect like it should while it was in the Mark VII with no idle surge. Now that its in my mustang it does it some times...The first vid below (ignore my oil pressure gauge I was gonna post that in another thread about my pressure sender but I put in a new one and it works as it should now, my car just happen to do some idle surging while I was recording the gauges..) at around 30+seconds youll start to here it idle up and down and the batt gauge moves with it. But when I first crunk it up it didnt rev high or anything (it does rev high when I crank it at one point in the 2nd vid) itll only do it some time. It likes to do it if I get on it then come to a stop kind of quick... but if i just touch the gas slightly itll stop usually. What you guys think the prob is?

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[jrichker]

See the "Surging Idle Checklist” for help with all your idle/stall problems. You can guess at the problem and throw parts at it, or you can use the checklist to help you find the problem quickly and inexpensively. It’s free and doesn’t cost anything: at last count there were more than 103,000 visits and still climbing

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.